1 /* 2 * Copyright 2015 Google Inc. 3 * 4 * Use of this source code is governed by a BSD-style license that can be 5 * found in the LICENSE file. 6 */ 7 8 #include "SkSpinlock.h" 9 10 #if SK_CPU_SSE_LEVEL >= SK_CPU_SSE_LEVEL_SSE2 11 #include <emmintrin.h> 12 static void pause() { _mm_pause(); } 13 #else 14 static void pause() { /*spin*/ } 15 #endif 16 17 void SkSpinlock::contendedAcquire() { 18 // To act as a mutex, we need an acquire barrier when we acquire the lock. 19 while (fLocked.exchange(true, std::memory_order_acquire)) { 20 pause(); 21 } 22 } 23
